Railway spring suspension

ABSTRACT

Air spring apparatus consisting of two axially aligned cylinders connected by an elastomer ring which provides an air seal. The shear capacity of the ring is slight permitting relatively free axial movement between the cylinders but is substantially incompressible to compression loads to prevent relative lateral movement of the cylinders.

United States Patent [72] Inventor Albert G. Dean Narberth, Pa.' [21]Appl. No. 795,218 [22] Filed Jan. 30, 1969 [45] Patented May 25, 1971[73] Assignee The Budd Company Philadelphia, Pa.

[54] RAILWAY SPRING SUSPENSION 1 Claim, 3 Drawing Figs.

[52] US. Cl 267/3, 105/197B, 105/199R, 267/33, 267/34, 267/35, 267/65R[51] Int. Cl B6lf 5/04, F16f3/10, F16f 13/00 [50] Field of Search105/197, 199,197 B; 267/3, 4, 33, 34, 35, 65 R [56] References CitedUNITED STATES PATENTS 811,622 2/1906 Downer 1 05/197 2,896,551 7/1959Lich 105/199 3,012,521 12/1961 Lich... 105/141 3,045,998 7/1962 Hirst...267/3 3,262,693 7/1966 l-Iirst... 267/3 3,361,087 l/1968 Dean 105/199X3,491,702 1/1970 Dean 105/199 Primary Examiner-Arthur L. La PointAssistant Examiner-Howard Beltran Attorneys-Thomas I. Davenport, EdwardM. Farrell, Alford L. Trueax, Jr. and William R. Nolte ABSTRACT: Airspring apparatus consisting of two axially aligned cylinders connectedby an elastomer ring which provides an air seal. The shear capacity ofthe ring is slight permitting relatively free axial movement between thecylinders but is substantially incompressible to compression loads toprevent relative lateral movement of the cylinders.

IIIIIIIIIIIIIIIIIII Patented May 25, 1971 3,580,557

2 Sheets-Sheet l INVENTOR. BY ALBERT G. DEAN UM M AGENT RAILWAY SPRINGSUSPENSION Reference is made to applicants copending application Ser.No. 659,948, filed Aug. 11, 1967, entitled Series Pneumatic and CoilSpring Assembly," now US. Pat. No. 3,49l,702, issued .Ian. 27, 1970, andassigned to the same assignee as the present invention. This copendingapplication discloses a combined pneumatic and structural coil springsuspension apparatus disposed between railway car truck and a vehiclebody above. The pneumatic spring comprises flexible bellows which restupon an inverted downwardly cupped spring seat which fits over the topof the structural coil springs. While the latter coil springs areeffective to resist some of the lateral movement of the pneumaticportion of the suspension system, as a unit, it has been found that thebellows per se is subject to undesirable lateral excursions.

It is an object of this invention, therefore, to provide an improvedpneumatic air spring apparatus which avoids one or more of thedisadvantages of the prior-art arrangements and which reducescomplications and improves durability.

In accordance with the invention, the pneumatic spring apparatus of thepresent invention comprises first and second cylinder means ofdissimilar diameters connected by elastomer ring means to provide an airseal. Each of the first and second cylinder means is closed at one ofits ends by an end wall. The elastomer ring means interconnecting thesidewalls of the first and second cylinder means are substantiallyincompressible to forces applied laterally but are yieldable in shearvertically as a result of axial movement between the cyindrical wallportions of said first and second cylinder means.

For better understanding of he present invention together with other andfurther objects thereof, reference is had to the following descriptiontaken in connection with the accompanying drawings and its scope will bepointed out in the appended claims.

ln the drawings,

FIG. 1 is a partial side elevation, with parts broken away in section,of a portion of a railway vehicle and its supporting truck at one end;

FIG. 2 is a top plan view of the assembly shown in FIG. 1 with portionsof the floor structure of the vehicle body removed;

FIG. 3 is an enlarged transverse section taken along the line 3-3 ofFIG. 2.

One corner of a car body is shown as having a side sill structure 11, acenter sill structure 12, floor beam structure 13, FIG. 3; and car bodybolsters 14. The bolsters are spaced apart longitudinally.

A railway truck of the same type as that referred to in the aboveidentified application is shown as comprising said frame members 21supporting a transverse truck bolster 22. The side frame members aresupported at their opposite ends on axles 23, and wheels 24. Each wheelhas associated therewith a brake assembly indicated by number 25. Theouter side portion of the truck bolster 22 is recessed, FIG. 3, toaccept a lower spring support 26 to receive vertically disposed coilspring assembly means 27. The latter coiled spring means are shown asincluding a heavy outer coil spring 29 and an inner light coil spring 30of less diameter than the former. The lower ends of both coil springs29, 30 rest upon a lower core-flanged positioning plate 31. A like upperpositioning plate 32 rests on the top of the coil springs 29, 30 andcarries the improved pneumatic spring means 35 in straight series withsaid coil spring assembly means 27 therebelow.

The improved pneumatic spring apparatus 35 comprises a top cuplike means36 and a coaxially aligned bottom cuplike member 37 of smaller diameterthan the top member, which are interconnected by means of an elastomericring means 39. The top cut member is shown as including an end wall 40with downwardly extending generally cylindrical sidewalls 41, whereasthe bottom cup member 37 includes a top end wall 42 with a downwardlyextending cylindrical wall 43. The top wall 42 of the lower cup membercarries the aforementioned coreflanged positioning late member 32 on itslower surface and supports a SOild resi lent bumper pad 44 on its uppersurface.

The generally cyindrical sidewalls 41 of the top cuplike member 36overlaps the sidewall 43 of the lower cup member 37 to thereby enablethe elastomer ring means to seal the space therebetween against airleakage.

In order to provide a suitable source of air supply to the pneumaticsuspension means 35 a conduit 47 extends from a fitting 48 opening intoa reservoir R formed by the bolster member 22, to fitting 49 extendingthrough sidewall 41 of the upper cup member at its upper end. Thepressure within pneumatic chamber 35 thus formed by the upper and lowercup members and seal 39 may be regulated in a desired manner accordingto the car loading to maintain fixed or varying floor heights of thecar. The means for regulating such pressure is well known in the art andis a usual accessory of air spring installations.

With further specific reference to elastomeric ring means 39, FIG. 3, itshould be noted that the same is of a material composition which enablesthe same to yield readily in shear vertically as a result ofdifferential telescopic vertical movement of sidewalls 41, 43. The ringmeans also have the property of being substantially incompressible as aresult of loads applied by the opposed sidewalls in a direction normalto said sidewalls and transverse to the major axis of coil springs 29,30. It should be noted further that the latter sidewalls 41, 43 of thepneumatic cup members extend downwardly so that the ring means 39 islocated at about midheight of the helical coil springs 35. Thus underlateral action of the car body 10 relative to the truck 20, and with theelastomeric ring so located, the ring provides in effect transversefixity of the air spring due to the incompressibility of the ring andits location along the vertical length of the coil springs 29, 30. Thisconstruction thereby eliminates the need of radius rods in prior artconstructions. In the event of loss of air pressure the elastomeric ring39 will deflect in shear until the resilient bumper pad 44 contacts theupper cup end wall 40. The vehicle ride will then be according to thecharacteristics of the mechanical coil spring 29, 30.

While there has been described what at present is considered to be thepreferred embodiment of this invention, it will be obvious to thoseskilled in the art that various changes and modifications may be madetherein without departing from the invention and it is therefore aimedin the appended claims to cover all such changes and modifications asfall within the true spirit and scope of the invention.

1 claim:

1. Spring apparatus for supporting a load comprising, pneumatic springmeans having first and second container means for enclosing acompressible medium therebetween, each said first and second containermeans having a sidewall portion and a top wall portion, resilient bumperpad means interposed between the top wall portion of each said first andsecond container means, the sidewall portion of said first containermeans being of greater diameter than, and overlapping, the sidewallportion of said second container means, elastomer ring meansinterconnecting the sidewall portion of said first container means tothe sidewall portion of said second container means to provide a sealbetween said first and second container means, said ring means beingsubstantially incompressible to forces applied normal to the sidewallportions of said first and second container means, said ring means beingyieldable in shear as a result of relative axial movement between saidsidewall portions of said first and second container means, coil springmeans engaging said second container means, said pneumatic spring means,said coil spring means, and said resilient bumper means being arrangedin direct series arrangement, said sidewall portion of said first and ofsecond container means encircling said coil spring means, said elastomerring means being positioned between said sidewall portion of said firstmember and said sidewall portionof said second member at approximatelymidheight of said coil spring means.

1. Spring apparatus for supporting a load comprising, pneumatic springmeans having first and second container means for enclosing acomPressible medium therebetween, each said first and second containermeans having a sidewall portion and a top wall portion, resilient bumperpad means interposed between the top wall portion of each said first andsecond container means, the sidewall portion of said first containermeans being of greater diameter than, and overlapping, the sidewallportion of said second container means, elastomer ring meansinterconnecting the sidewall portion of said first container means tothe sidewall portion of said second container means to provide a sealbetween said first and second container means, said ring means beingsubstantially incompressible to forces applied normal to the sidewallportions of said first and second container means, said ring means beingyieldable in shear as a result of relative axial movement between saidsidewall portions of said first and second container means, coil springmeans engaging said second container means, said pneumatic spring means,said coil spring means, and said resilient bumper means being arrangedin direct series arrangement, said sidewall portion of said first and ofsecond container means encircling said coil spring means, said elastomerring means being positioned between said sidewall portion of said firstmember and said sidewall portion of said second member at approximatelymidheight of said coil spring means.